The temporary design of hairstyles for a longer period up to several days usually requires the application of setting active ingredients. Hair treatment agents which are used for temporary shaping of the hair therefore play an important role. Corresponding agents for temporary deformation usually contain synthetic polymers and/or waxes as the setting active ingredient. Agents for supporting the temporary shaping of keratin-containing fibers can be formulated, for example, as a hair spray, hair wax, hair gel or hair mousse.
The most important property of an agent for the temporary deformation of hair, hereinafter also referred to as a styling agent, is to give the treated fibers in the newly modeled shape, i.e., a shape impressed on the hair, the strongest possible hold. One also speaks of strong hairstyle hold or the high degree of hold of the styling agent. The hairstyle hold is essentially determined by the type and amount of the setting active ingredients used, wherein, however, an influence of the other ingredients of the styling agent may also be given.
In addition to a high degree of hold, styling agents must meet a whole series of other requirements. These may be broadly subdivided into properties on the hair, properties of the particular formulation, e.g., properties of the foam, of the gel or of the sprayed aerosol, and of properties which affect the handling of the styling agent, wherein the properties on the hair are of particular importance. Particularly noteworthy are moisture resistance, low tack and a balanced conditioning effect. Furthermore, a styling agent should be universally applicable for all hair types and mild to hair and skin.
A variety of synthetic polymers which are used in styling agents have already been developed as setting active ingredients to meet the different requirements. The polymers can be subdivided into cationic, anionic, nonionic and amphoteric setting polymers.
European Patent Application EP 3 069 709 A1 describes hair cosmetic polymer mixtures which contain, in addition to an oxyalkylene polymer, the hydrophobically modified (meth)acrylic acid copolymer having the trade name Luvigel Fit (INCI: Acrylates (C10-30) Alkyl Methacrylate Copolymer).
Hair fixing agents based on copolymers of styrene with (meth)acrylic acid and/or their esters are described in the international patent application WO2012/168035 A1.
Ideally, when applied to hair, the polymers provide a polymer film which, on the one hand, gives the hairstyle a strong hold but, on the other hand, is sufficiently flexible not to break under stress. If the polymer film is too brittle, it results in the formation of so-called film plaques, that is, residues that detach during the movement of the hair and give the impression that the user of the corresponding styling agent might have dandruff. Similar problems arise when waxes are used as a setting active ingredient in the styling agent. If the styling agent is a gel or a paste, the polymers should also have thickening properties.